Basic scientific research
- Content of the result. Triplet spin-valve effect
|Fig. 1. Electron micrograph of the cross section of the
||Fig. 2. Dependence of the critical temperature Tc of superconductor-ferromagnet nanostructures on magnetic field direction.
- Brief description. A triplet spin-valve effect, which was theoretically predicted for superconductor-ferromagnet heterostructures, was observed. Experimental studies of multilayer Nb/Cu41Ni59/ncNb/Co/CoOx structures reveal unusual features of the angular dependences of the magnetoresistance of these structures. Variations in the critical temperature in a magnetic field exhibit a deep minimum of Tc resulting from the occurrence of the triplet spin-valve effect. The observed effect can be used to design switching elements for spintronics and nanoelectronics.
- International impact. The observed effect was presented as a report at the international conference ICSM-2012 "International Conference on Superconductivity and Magnetism," Istanbul, in April 2012 and in the manuscript "Observation of long-range triplet pairing in a superconductor-ferromagnet spin-valve structure" accepted for publication in the journal Physical Review (A.Sidorenko, V. Zdravkov, R. Morari, et.al.).
- Content of the result. Extraordinary thermoelectric characteristics of Bi1-хSbх wires
- Brief description. Bi1-хSbх nanowires in a glass envelope with a high positive-polarity thermopower in the range of low temperatures and weak magnetic fields have been prepared; this offers the prospect of using them as p-branches of thermoelectric energy converters for various purposes.
Bi-2at%Sb nanowires in glass envelope: 1- d= 300 nm, 2- d= 400 nm, 3- d= 600 nm, 4- d= 1600 nm
- International impact. NIKOLAEVA, A. A.; KONOPKO, L. A.; HUBER, T. E.; BODIUL, P. P.; POPOV, I.A. Prospects of nanostructures Bi1−xSbx for thermoelectricity. Journal of Solid State Chemistry. (2012). http://dx.doi.org/10.1016/j.jssc.2012.03.063 (IF: 2,261)
- Content of the result. Anisotropic thermoelectric generator based on semimetal wires in a glass envelope
Fig. 1. (a) Anisotropic thermal element prepared by winding a single crystal in a glass envelope in a flat spiral; (b) anisotropic thermoelectric energy converter.
- Brief description. A breadboard version of an anisotropic thermoelectric generator based on Bi wires in a glass envelope which operates through a temperature gradient created by the warmth of the human body has been first developed, designed, and constructed. It can be used as a power source in hearing aids. According to calculations, the thermopower of the anisotropic thermoelectric generator based on wires in a glass envelope must be 800-1000 mV. The proposed version of the anisotropic thermoelectric generator based on wires in a glass envelope compares favorably with known ring and spiral anisotropic thermoelements and with anisotropic thermoelectric generators based on Bi2Te3 and TE with extremely high thermopower anisotropy.
- Content of the result. A technique for preparing GaP nanoparticles
Scanning tunneling microscopy image (a) and electron diffraction pattern (b) of GaP nanoparticles. AFM image of the composition of poly(2-vinylpyridine) and a GaP suspension in ethanol (c).
- Brief description. A new technique for preparing GaP nanoparticles with high luminescence intensity at a wavelength of 410 nm has been developed. The innovative component of the developed method is the use of gallium acetylacetonate as a source of gallium atoms during the synthesis of GaP nanoparticles. The developed technique makes it possible to prepare gallium phosphide nanoparticles for designing emission sources with improved efficiency.
- ResonanceRUSU Emil, PÎŞKIN Serghei, URSACHI Veaceslav, IACOB Mihai, BALLATO John, GUŢUL Tatiana, MD patent 483, September 30, 2012.
- Content of the result. A technique for testing hygroscopic pyrotechnic compositions used for inducing artificial precipitation.
- Brief description. The testing technique developed in the IEIN is based on using an aerodynamic stand; it gives the possibility to test various hygroscopic pyrotechnic compositions under laboratory conditions similar to a real cloud environment, which are used for inducing artificial precipitation. Cloud seeding with hygroscopic pyrotechnic compositions aimed at increasing the amount of precipitation in order to prevent drought can also be carried out using rocket technologies. In Moldova, there is the Special Service for Active Influences on Hydrometeorological Processes, which performs operations for hail protection using a rocket technology. Along with hail suppression, based on this technology, this Service is capable of performing operations aimed at stimulation of artificial precipitation.
The economic feasibility of this development is that the works on inducing artificial precipitation will involve hygroscopic pyrotechnic compositions, which have been subjected to an independent verification and validation (testing) and can be used to stimulate additional rainfall, especially in dry years, which will generally provide a significant support to the agricultural sector of the national economy.
Distribution of water particles derived in a cloud chamber at positive temperatures (0 to +10 0С)before introducing a hygroscopic composition.
|Distribution of water particles derived in a cloud chamber at positive temperatures (0 to +10 0С) after introducing a hygroscopic composition of the LOZA type (Bulgaria).
- Content of the result. Тechnology for obtaining red algae Porphyridium cruentum stimulated by CdSe quantum dots covered with thioglycerol
|FTIR transmission spectra of (1) thioglycerol and (2) typical CdSe/TG quantum dots
||Absorption spectra of phycoerythrin of (1) Porphyridium cruentum and (2) a hydric colloidal solution of CdSe QDs.
||Room-temperature photoluminescence spectra comparing CdSe QD hexan solutions: (1) colloidal CdSe/OA dots with 2.7 nm; (2) colloidal CdSe/OA dots with 3.5 nm; and (3) an aqueous solution of phycoerythrin of Porphyridium cruentum biomass
- Brief description. An increase in the amount of biomass was observed owing to the interaction of Porphyridium Cruentum and Spirulina Platensis with CdSe nanoparticles in a concentration range of 4.06.0 mg/l. The amount of biomass increased by 34-47% because of the light absorption by QDs in UV-visible absorption spectra. Nanoparticles formed with phycoerithrin improve the efficiency of light absorption due to the complex hybrid photosynthesis. The absence of toxic effects of CdSe QDs and an increase in the amount of biomass give the possibility to utilize them in environmental engineering. CdSe QDs absorbed by microalgae can be utilized in water detoxification in order to eliminate the toxic effect of cadmium. In addition, hybrid systems composed of CdSe QDs and phycoerithrin increase the efficiency of solar cells based on photosynthetic reaction centers.
- International impact. RUDIC, V.; CEPOI, L.; GUTSUL, T.; RUDI, L.; CHIRIAC, T.; MISCU, V.; SADOVNIC, D.; NICORICI, A. Red algae Porphyridium cruentum growth stimulated by CdSe quantum dots covered with thioglycerol. J. Nanoelectron. Optoelectron. 7(7), 681-687 (2012).
- Content of the result. Ultrathin suspended membranes of GaN
- Brief description. Ultrathin suspended GaN membranes designed by focused ion beam treatment of the GaN epilayer surface with subsequent photoelectrochemical etching have been prepared. This technological approach allows preparing ultrathin membranes as well as supporting micro/nano-columns in a controlled fashion. The analysis of the spatial and spectral distribution of microcathodoluminescence demonstrates that the membranes exhibit mainly yellow luminescence. These results pave the way for the fabrication of ultrathin suspended GaN membranes for MEMS/NEMS applications.
- International impact. TIGINYANU, I. M.; POPA, V.; STEVENS-KALCEFF, M. A.; GERTHSEN, D.; BRENNER, P.; PAVLIDIS, D. Physica Status Solidi (RRL) - Rapid Research Letters. 2012, 6(4), 148-150. (IF: 2,66)
- Content of the result. A device for treating infected cavities with broadband photon radiation
- Brief description.Results of irradiation of extensively drug-resistant wild MT strains isolated from patients of the Vorniceni tuberculosis hospital and a reference strain H37RV.
The in vitro results give the possibility to propose a method for treating infected cavities with broadband photon radiation for clinical trials for the stabilization of the process and the rehabilitation of degradation cavities in fibro-cavernous tuberculosis, in particular, for preoperative preparation of patients.
- Impact. The device for the treatment of infected cavities with broadband photon radiation has been patented: Yu. Nica, L. Pogorel'skii, E. Maksimov, P. Deshanu, K. Yavorskii, V. Bologa, V. Nakhaba, and E. Tsymbalar, A device for treating infected cavities of internals with photon radiation, MD patent 540 (13Y), August 30, 2012.
- Content of the result. A sensor for water salinity measurements.
- Brief description. The sensor simulates neural structures and encodes parameters on the basis of the principles of nonlinear dynamics (similar to natural systems, where neurons serve as sensors). This result opens new lines of research in the unexplored domains of design, implementation, and testing of biomimetic sensors based on nonlinear (chaotic) dynamics for environmental measurements (nonlinear dynamic systems based on nanodevices for engineering applications). This result was obtained in cooperation with associate member of the Romanian Academy of Sciences, Prof. H.-N. Teodorescu (Technical University of Iasi "G. Asachi," Romania) and Dr. V. Cojocaru (Gitsu Institute of Electronic Engineering and Nanotechnology, Academy of Sciences of Moldova).
- International impact. Research results were published at the Third International Conference on Emerging Security Technologies IEEE 2012: H.N. Teodorescu and V. Cojocaru, Biomimetic chaotic sensors for water salinity measurements, simulator, and application, The Emerging Security Technologies (EST), September 5-7, 2012, Lisbon, Portugal Proceedings 2012.
A Model Approval Certificate for gage pressure sensors TP-12E2-10 was received and entered in the State Register of measuring instruments under no. 1-0797:2012.